أن كرة السلة بما تتضمنه من مهارات حركية متنوعة تتطلب من ممارسيها امتلاك عدد من القدرات الحركية الخاصة وبشكل خاص التوافق العضلي العصبي والرشاقة والقوة المميزة بالسرعة، فضلاعن قدرات الإدراك الحس- حركي (إدراك المكان وقوة دفع الكرة سواء بالطبطبة العالية أو الواطئة .... الخ ) لذا تكمن أهمية البحث في إيجاد الطرق والوسائل التي تطور قدرة الطالبة على إدراك قوة دفع الكرة والإحساس بها أثناء تعلم وتدريب الطبطبة بأنواعها بإدخال تمرينات إدراك قوة الذراع ومن ثم تأثيرها على مستوى أداء مهارة الطبطبة في كرة السلة . ومن خلال ملاحظة أداء الطالبات في دروس كرة السلة وجدنا ضعف في أداء مهارة الطبطبة سواء كان من الثبات أو من الحركة وعدم إدراك القوة اللازمة لأداء هذه المهارة بصورة صحيحة مما يؤدي إلى ارتباك في الأداء, ويدفع الطالبة إلى إعطاء قوة غير مناسبة وبالتالي ارتفاع الكرة إثناء الطبطبة إلى أعلى من مستوى الحوض أو إعطاء قوة غير كافية مما يؤدي انخفاض مستوى الطبطبة ، وهذا يرجع إلى قلة الإدراك والإحساس بالقوة المناسبة لدفع الكرة ، وهنا تكمن مشكلة البحث. وهدفت الدراسة إلى معرفة تأثير تمرينات إدراك قوة الذراع على مستوى أداء مهارة الطبطبة في كرة السلة . استخدم المنهج التجريبي على طالبات المرحلة الرابعة البالغ عددهم (25) طالبة قسموا على مجموعتين ( تجريبية وضابطة ) طبقت التجريبية تمرينات إدراك قوة الذراع , خلال الطبطبة (دفع الكرة) أدخلت في القسم الرئيسي الجانب التطبيقي من الدرس وبواقع ( 10 ) دقائق وعلى مدى 8 أسابيع . فاستنتج أن لتدريبات إدراك قوة الذراع تأثيراً ايجابياً في تطوير مهارة الطبطبة في كرة السلة لدى إفراد عينة البحث. وتوصي الباحثات بالتركيز على التمارين خاصة بادراك قوة الذراع خلال الدرس للارتقاء بمستوى أداء المهارة .
The response of the combustor’s liner to the air-flow that passes through it is the key reason for the combustion chambers noise, hence the instabilities of those chambers that decreases the mechanical efficiency of such sections, by increased its mechanical vibrations, which increases the failure rate created during originating of the cracks spreading by the shakes producing by the series of high-level frequencies. Accordingly, any work debating the impact of the context of liners in the combustion chamber can provide grasping for the combustion noise generated by the undesirable vibrations, and benefits the industrial firms to design an ideal production procedure which increases the lifespan of the combustor. The goal of this wo
... Show MoreThe study aimed to measure the concentration of some heavy metal elements and represented by (Pb, Cd,Cu) through the use of atomic absorption spectrometer Flame AAS-7000 type SHIMADZU underwent a process modeling to twelve samples from the soil of electricity Dezlat al Jadiriyah station in the Baghdad University compound at a depth of 30-60 cm from the surface and divided the samples into two groups first included six samples from inside the station while the second included six samples from outside the station. For the element of Pb was higher concentration reached by 29.32ppm and less concentration 17.56ppm. were elements Cd and Cu are growing and less and proportions of certain while the highest concentration of copper 9.69 ppm and le
... Show MoreThe design, construction and investigation of experimental study of two compound parabolic concentrators (CPCs) with tubular absorber have been presented. The performance of CPCs have been evaluated by using outdoor experimental measurements including the instantaneous thermal efficiency. The two CPCs are tested instantly by holding them on a common structure. Many tests are conducted in the present work by truncating one of them in three different levels. For each truncation the acceptance half angle (θc) was changed. Geometrically, the acceptance half angle for standard CPC is (26o). For the truncation levels for the other CPC 1, 2 and 3 the acceptance half angle were 20o, 26o and 5
... Show More An experimental and computational study is conducted to analyze the thermal performance of heat sinks and to pick up more profound information in this imperative field in the electronic cooling. One important approach to improve the heat transfer on the air-side of the heat exchanger is to adjust the fin geometry. Experiments are conducted to explore the impact of the changing of diverse operational and geometrical parameters on the heat sink thermal
performance. The working fluid used is air. Operational parameters includes: air Reynolds number (from 23597 to 3848.9) and heat flux (from 3954 to 38357 W/m
2 ). Conformational parameters includes: change the direction of air flow and the area of conduct
A field experiment was carried out in one of the orchards of Al-Qassim district in Babel Governorate to find out the ability of a locally manufactured platform to serve palm trees by working in flat and uneven orchard land, palm tree heights of 4, 8, and 12 meters, and it performs pollination, pruning and harvesting services. The time of ascent and descent, the palm service, and the palm/hour productivity were measured. A randomized complete block design with three replications used a split split-plot arrangement. The nature of the land (flat or uneven) represented the main plots, the height of the palm trees (4, 8, 12) meters, the sub-plots, and the palm service operations (pollinati
The effect of internal acoustic excitation on the leading-edge, separated boundary layers and the aerodynamic performance of NACA23015 cross section airfoil are examined as a function of excitation location with ranging frequency range (50-400) Hz of the introduced acoustic. Tests are separately conducted in two sections, open type wind tunnels at the Reynolds number of 3.3x105 for measurement at angle of attack (0, 3, 6, 9 &12) deg. and 3x104 for the visualization at angle of attack (12) deg. based on the airfoil chord. Results indicated that the excitation frequency and the excitation location are the key parameters to alter the flow properties and thus to improve the aerodynamic performance. The most effective excitation frequency
... Show MoreFor over a century, the global consumption of asphalt binder in asphalt mixture production has been substantial. In the Heet region (west of Iraq), two distinct forms of natural asphalt (NA) deposits exist: rock asphalt and sulfur spring asphalt. This study focused on using NA sourced from sulfur springs. The aim was to investigate the potential of incorporating NA into local asphalt mixtures. To achieve this, NA was heated to 163°C for varying durations. After heat treatment, laboratory tests were conducted on NA. The findings suggest that by heating NA for 20 hours, it conforms to Iraqi specifications in terms of physical properties. Furthermore, compared to conventional petroleum asphalt, treated NA showed greater
... Show MoreIt is through a review of conversion of vegetable oils into glycidyl ethers focusing on their roles in achieving sustainability and improved epoxy resin performance. It involves functionalization of triglycerides in the form of epoxidation followed by glycidylation and yields bio-based monomers having improved mechanical as well as thermal properties. The review covers the underlying chemistry, production drivers, industrial applications, and future issues, supported by quantitative data and comparative studies. In addition, it integrates recent data on catalyst choice, feedstock flexibility, and environmental performance factors of bio-based resins, indicating their suitability for replacing traditional petroleum-based components.<
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